Interesting Contents of the Working Survey Database
- The 2MASS working survey database (WSDB) contains all source extractions
from pipeline processing which meet minimum quality requirements
(specifically a quality score > 3).
- In contrast, the release catalogs are selected to produce
unique apparitions of highly reliable sources (SNR>7.0).
- The second incremental release contained about 40% of the sources
available in the WSDB at the time of release.
Contents of the unreleased data
- The WSDB will contain approximately one billion unreleased sources.
- Half will be false sources.
- The pipeline was tuned to produce a 1:1 ratio
of false to real sources to ensure completeness.
- Users have many factors such as
multi-bandedness, chi-squared, detection flags,
optical associations, and the atlas images
to evaluate the reality of a source.
Figure
1 -- WSDB source J-band source counts (b>85)
- Sources between 5<SNR<7 will be fairly reliable
and astrophysically valuable.
- 2MASS fluxes at positions of known sources
- Statistical star-count and population studies
- Extragalactic counts rise steeply
- ~25% of the sources will be repeated observations,
including including scan overlaps and re-observation of
lower quality tiles.
- Include unreleased apparitions of high SNR sources.
- Enables improvement of catalog sensitivity by
sqrt(2) for 20% of the sky.
- Enables time variability and proper motion
studies
agenda
